The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
It can be appreciated that fixed-blade hunting broadhead have been in use for years. Typically, fixed-blade hunting broadhead are comprised of NAP Thunderhead, Nitron, Razorcaps, Muzzy 3 and 4 blade, Muzzy Phantom, ABC Sonic, Interloc, Fuse, Steel force, Grim Reaper, etc. These and others are covered in the prior art, for example, U.S. Pat. No. 2,137,014, issued in November of 1938 to Brochu; U.S. Pat. No. 2,686,055, issued in August of 1954 to Peltz; U.S. Pat. No. 2,829,894, issued in April of 1958 to Henkel; U.S. Pat. No. 2,940,758, issued in June of 1960 to Richter; U.S. Pat. No. 3,741,542, issued in June of 1973 to Karbo; U.S. Pat. No. 3,756,600, issued in September of 1973 to Maleski; U.S. Pat. No. 3,854,723, issued Dec. 17, 1974, to Wilson; U.S. Pat. No. 3,887,186, issued in June of 1975 to Matlock; U.S. Pat. No. 3,915,455, issued in October of 1975 to Savora; U.S. Pat. No. 4,146,226, issued in March of 1979 to Sorensen; U.S. Pat. No. 4,169,597, issued in October of 1979 to Maleski; U.S. Pat. No. 4,175,749, issued in November of 1979 to Simo; U.S. Pat. No. 4,210,330, issued in July of 1980 to Kosbab; U.S. Pat. No. 4,349,202, issued in September of 1982 to Scott; U.S. Pat. No. 4,381,866, issued in May of 1983 to Simo; U.S. Pat. No. 4,410,184, issued in October of 1983 to Anderson; U.S. Pat. No. 4,529,208, issued in July of 1985 to Simo; U.S. Pat. No. 4,537,404, issued in August of 1985 to Castellano et al.; U.S. Pat. No. 4,671,517, issued in June of 1987 to Winters; U.S. Pat. No. 4,807,889, issued in February of 1989 to Johnson; U.S. Pat. No. 5,165,697, issued Nov. 24, 1992, to Lauriski et al.; U.S. Pat. No. 6,306,053, issued Oct. 23, 2001, to Liechty, II; and U.S. Pat. No. 6,530,853, issued Mar. 11, 2003, to Giannetti.
The main problem with conventional fixed-blade hunting broadhead is accuracy. When it comes to hunting arrowheads (a/k/a broadheads), there are two basic types in use today. The “fixed” blade is one in which all cutting surfaces are exposed and there is no moving blades or other parts once the broadhead has been assembled and affixed to the arrow. The other is the “mechanical” or “expandable” in which some sort of blade deployment system(s) is used regardless if some fixed blade is also affixed to the unit.
The mechanicals started displacing a good share of the fixed-blade market for the sole reason of advertised superior flight and accuracy characteristics over the fixed-blade designs. Since there was significantly less exposed blade surface with the mechanical designs, this made sense. Bow hunters were always looking for a broadhead that would behave in flight, exactly like their target practicing non-bladed field points. Some of the better designed mechanicals (like the Aftershock Archery “Hypershock”) would actually do this.
In the world of bowhunting, there are certain factors involved in a successful harvest of game that are indisputable. Three primary and very crucial factors come into light. Accuracy is one. If the broadhead does not have accurate flight characteristics, the chance of hitting the optimum location of the vital organs is severely compromised. An overwhelming majority of fixed-blade designs suffer from inaccurate flight caused primarily by inadequate aerodynamic principals applied to the design, as well as designs that create an unacceptable amount of aerodynamic drag. Most of this drag comes from uncontrolled turbulence created by the leading edge and/or tip as well as blades inserted into the tip, the main cutting blade design, location, angles and indexing of those blades to the cutting tip and/or ferrule shape as well as positioning therein. Some designs even employ tabs, twisted blades, or bent trailing edges to impart “spin” into the arrow assembly to facilitate the in-flight averaging of arrow assembly issues and/or misalignments in the hope of gaining tighter groups in the target.
Regardless if the “grouping” of arrows being shot into a target does improve, physics as well as testing reveals that the aerodynamic drag required to spin the assembly in flight is requiring that a remarkable portion of the kinetic energy imparted by the bow to the arrow assembly be used to do this “spinning.” Whatever portion of the broadhead's blades and the arrow's rear feathers or vanes that are not in perfect rotational angles and harmony with the broadhead's spinning fails to match those imparted RPM's, results in the assembly turning into a centrifugal air pump, which in turn requires ever greater amounts of kinetic energy to be drained from the forward momentum of the assembly. This consequently results in a lower amount of downrange kinetic energy and imparts (at the very least) a vertical drop and loss of speed at target not seen with the equivalent weight field point.
Accuracy has been partially addressed by some fixed-blade designs by reducing the total cutting area and/or cutting diameter of the blades. This reduction in blade area will help improve accuracy by reducing the kinetic energy loss attributed to drag, but the lethality and subsequent killing power of the broadhead has been severely compromised. Another problem with conventional fixed-blade hunting broadhead is that the insufficient structure or reinforcing structure of razor-type tips causes not only blade deformation as well as blade loss issues, it can also severely compromise the penetrating power of the broadhead into hard objects, such as bone. There are two primary types of so-called razor-sharp tips (a/k/a cut-on-contact). The first type dates back to stone arrowheads, whereby the main blade and its cutting surface come all the way up to form the tip. The cutting angle or curved shape is irrelevant. The stone has been replaced by steel in the modern art (as well as using more than two cutting surfaces in many designs), but the principle and ease of manufacture has remained the same.
The issue with this design is weight, strength at the tip, and inaccuracy caused by excessive surface area. The other primary cut-on-contact design currently in use employs add-on blades, either to the tip directly or sharpening of the tip material used by either the ferrule or another material of tip affixed to the ferrule. These designs are prone to blade-retention issues as well as kinetic energy loss due to mechanical movement of the fastening method and/or retention in their corresponding channels or slots.
Another problem with conventional fixed-blade hunting broadheads is penetration performance. Compared to firearm hunters, the bowhunter has very limited energy in his/her arrow assembly and has to deal with real world issues concerning hitting bone prior to contacting the vital organs. The current and prior art will show that many designs have only the main blade-cutting surface extending forward and forming the tip. These are not considered bone-shattering tips and consequently go into a “wedging” condition as they attempt to travel through bone. This is already assuming that the leading edge of the blade is not deformed or broken immediately upon impact with hard bone. This wedging occurs from a simple physics issue of a small (blade thickness only) cavity being cut into the bone and having the surface area of the broadhead constantly increase as it tries to pass through. Inherent of these designs, the blade(s) becomes continually wider, increasing surface area and friction starting from the moment of contact by the tip. The ferrule (if any) will only exacerbate the wedging issue further as it increases the total surface area, as well. Even the designs that stop the main blades short of the tip, where a tip (cutting, bone-shattering, or otherwise) is employed, that have ferrule cross-sections larger than the cavity the tip produced, will go into wedging condition, as well.
The first true non-wedging, bone-shattering tip/ferrule design was incorporated into the Aftershock Hypershock broadhead, whereby the ferrule and exposed blade cross-section directly behind the cutting tip was smaller than the cavity the tip would produce. While these devices may be suitable for the particular purpose to which they address, they are not as suitable for the bowhunter to have an accurate and energy-conserving, fixed-blade broadhead that will provide higher penetration coupled with a structurally sound non-deflecting blade-cutting area to take down wild game as fast and as humanly as possible.
In these respects, the aerodynamically and structurally superior, fixed-blade hunting arrowhead according to the present invention substantially departs from the conventional concepts and designs of the prior art and, in so doing, provides an apparatus primarily developed for the purpose of the bowhunter to have an accurate and energy-conserving, fixed-blade broadhead that will provide higher penetration coupled with a structurally sound, non-deflecting blade-cutting area to take down wild game as fast and as humanly as possible.